Domestic fireplace structure



N. ROBERTSON 1331596 DOMESTIC FIREPLACB STRUCTURE Filed March 14. 1927 Patented June 7, 1927.

UNITED STATES PATENT OFFICE.

NEIL ROBERTSON, OF VANCOUVER, BRITISH COLUMBIA, CANADA.

DOMESTIC FIREPLACE STRUCTURE.

Application filed March 14, 1927, Serial No. 175356, and in Canada February 2, 1927.

This invention relates to a fireplace structure for domestic buildings.

Its object is to provide a Construction which utilizes more etficiently the non-radiant heat at the rear and sides of a fireplace tiXture by setting up convection currents in contiguity With the vertical rear and side plates which form the boundary of the hearth space thus drawing an independent supply of fresh air into an apartment and lischarging it thereinto as a stream of warm air through grid covered apertures in the upper portion of the fireplace fixturep And moreover to effect this improvement by a simple Construction which effects its purpose at a fraction of the cost of some other 'devices designed for similar objects.

In carrying out this idea into practice I form an independent air flue around the three sides of the hearth space, the outer Wall of this air flue being the chimney brickwork as usual and-preferably with a firebrick 'facingg the vertical surfaces being gradually gathered in to form a diminishing area at the upper portion in order to meet ?he vertical walls limiting the hearth space at the rear and sides. These vertical fence or boundary walls I make of corrugated metal for the purpose of obtaining increased heating and radiating surface, and also adding to the strength of the Construction.

Thus a three-sided chamber tis formed around the hearth space 'diminishing at the rear wall in area from a maximum at the hearth level to a minimum at the top where the chimney brickwork of the fireplace boundary walls tends to intercept. The air fiue is in communication with an air conduit below, which leads to a fresh air supply. Thus a stream of fresh warm air is supplied to the apartment and the fuel ef ficiency of the fire-grate correspondingly improved.

The invention is clearly shown in the drawings herewith which form part of this application- Figure 1 being a front elevation of a fireplace in which my device is incorporated.

Figure 2 is a vertical section showing the smoke-fine and the fresh air flue.

Figure 3 is a sectional plan.

Taking the drawings in detail and noting that similar numerals in the different views indicate identical parts, 4 is the vertical front plate of a fireplace fixture, 5 being the mantel surrounding and surnountng same,

6 the usual brickwork of the chimney. 7 is the hearth which is bounded on the rear and sides by the vertically corrugated plate 8. This latter it will be noted is adapted to leave a separated air-space 9 on its sides and rear which is entirely cut off from the smokeflue at the rear by an angle iron 10 and in a similar or other suitable way at the sides which slope upwards from the rear 10 to the front at 11.

At the upper portion of the air flue there is on each side a grid covered aperture 12 opening into the apartment.

At the hearth level an aperture 13 is provided for the fresh air inlet. This is in communication with the vertical conduit 14: or any other suitable source leading to the atmosphere.

The chimney flue 15 is entirely separate from the air flue 9. The arrows in the latter show the direction of the air flow from the air supply to the apartment.

Having now particularly described my invention what I claim as my invention' and desire to be protected in by Letters Patent is: v

In a domestic-fireplace structure the combination comprising a vertical front plate having a grid-covered aperture in its upper portion, said aperture opening into the apartment, a 'vertical hearth boundary plate adapted to act as a rear and side fence to the hearth of the said fireplace, said boundary plate having vertical corrugations and being Secured by its front vertical edges to the said frontplate by a tight seam, the rear portion of said vertical boundary plate having a horizontally disposed angle iron along its top rear edge forming a jointat its inter'- section with the chimney brickwork, an air fine separate from the chimney at the rear and sides of said boundary plate, said air fiue at the rear of the said hearth extending from a. maximum width at the hearth level to a minimum width at the top of said boundary plate, an aperture in the hearth plate within said air flue, said aperture communicating with an air-fine below said hearth and with a fresh air supply, the said air-fiue being adapted to form an independent conduit between the said fresh air supply and the said grid covered aperture in the upper portion of .said front plate.

In testimony whereof I atfix my signature.

NEIL ROBERTSON. 

